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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Chemically modified poly(lactic acid): structural approach employing two distinct monomers

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Author(s):
Rigolin, Talita Rocha [1] ; Costa, Lidiane Cristina [1] ; Bettini, Silvia Helena Prado [1]
Total Authors: 3
Affiliation:
[1] Univ Fed Sao Carlos, Grad Program Mat Sci & Engn, Rod Washington Luiz, Km 235, BR-13565905 Sao Carlos, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: JOURNAL OF POLYMER RESEARCH; v. 28, n. 4 APR 2021.
Web of Science Citations: 0
Abstract

The chemical modification of poly(lactic acid) with different monomers has been investigated, since comparative studies of the use of two monomers are scarce in literature. The present study aims to determine the number of acid groups available after modification as well as their final molar mass. Therefore, maleic anhydride (MA) and glycidyl methacrylate (GMA) were grafted separately onto PLA in the presence of peroxide according to a 2(2) factorial design, where monomer and peroxide concentrations were varied. All reactions were carried out in the melt in a Haake rheometer. The acidity percentage and molar mass of the polymer were determined by means of acid group titration and size-exclusion chromatography, respectively. The thermal properties of the modified PLA were assessed using DSC. The results showed that the two different monomers modified PLA properties differently. Whereas GMA increased the molar mass and decreased the acidity percentage of PLA, the presence of MA had an opposite result. This finding has important implications on subsequent reactions. The independent variable peroxide concentration was which most affected acidity percentage when MA was used. On the other hand, when GMA was used the variable which most affected acidity percentage was the monomer concentration. (AU)

FAPESP's process: 08/04334-2 - Grafting of Maleic Anhydride onto Polypropylene by Reactive Processing, in Presence of Nanoparticles.
Grantee:Silvia Helena Prado Bettini
Support Opportunities: Regular Research Grants
FAPESP's process: 11/21313-1 - Study of the reaction kinetic and the addition of the metal deactivators in the grafting of maleic anhydride onto polypropylene in the presence and absence of the nanoparticles
Grantee:Silvia Helena Prado Bettini
Support Opportunities: Regular Research Grants